In auxiliary oil coolers in which coolant such as water passes through tubes for cooling externally moving oil, various approaches have been considered for minimizing or preventing blockage of the coolant tubes, with resultant overheating or failure of the associated engine.
Usually the auxiliary cooler assembly is secured directly or through a supplementary fitting to the engine block with appropriate gaskets interposed between the block and the auxiliary cooler. Generally the gaskets provide four flow paths to and from the block, namely an oil exit path, running from the block to the auxiliary cooler, an oil inlet path returning from the cooler to the block, a coolant exit opening running from the block to the auxiliary cooler, and a coolant inlet opening returning coolant to the block. Such flow paths and associated openings in the block, auxiliary cooler fittings and interposed gasket are clear-through openings. Particulate material which develops in the engine and radiator is frequently found in the coolant, is entrained therein and therefore passes into the tubes of the auxiliary cooler.
Although consideration has been given to interposing filtering or screening elements in the coolant lines and flow paths, no fully satisfactory solution to removal of the particles which have the capacity of blocking the auxiliary cooler tubes has been found.